Related Experiment Videos
Susceptibility of Chlamydia psittaci (ovis) to antimicrobial agents
Abstract:
Minimum inhibitory (MIC) and minimal lethal (MLC) concentrations of 30 antimicrobial agents were determined for field strains and for the A22 EAE vaccine strain of Chlamydia psittaci (ovis). No differences in susceptibility could be detected between strains. The antimicrobials could be divided into four groups. Group A had no effect on growth and development, Group B were bacteriostatic at concentrations in excess of 100 mg/l, Group C were bacteriostatic at concentrations of 10 mg/l or less but were bactericidal at concentrations above 10 mg/l and Group D were bactericidal at concentrations above 0.5 mg/l. The value of antimicrobials in aiding diagnosis and in the therapy of chlamydial abortion of ewes is discussed.
Insights
This study determined antimicrobial susceptibility for Chlamydia psittaci (ovis) strains, finding no differences between field and vaccine strains. Antimicrobials were categorized into four groups based on their effectiveness, informing diagnosis and therapy for ovine chlamydial abortion.
Area of Science:
- Veterinary Microbiology
- Animal Infectious Diseases
- Antimicrobial Resistance
Background:
- Chlamydia psittaci (ovis) causes significant economic losses in sheep farming due to ovine chlamydial abortion.
- Understanding the antimicrobial susceptibility of C. psittaci is crucial for effective disease management and treatment strategies.
- Field strains and vaccine strains may exhibit differential responses to antimicrobials, impacting therapeutic choices.
Purpose of the Study:
- To determine the minimum inhibitory (MIC) and minimal lethal (MLC) concentrations of 30 antimicrobial agents against field strains and the A22 EAE vaccine strain of Chlamydia psittaci (ovis).
- To categorize the tested antimicrobials based on their efficacy against C. psittaci.
- To discuss the implications of these findings for the diagnosis and therapy of chlamydial abortion in ewes.
Main Methods:
- Determination of MIC and MLC values for 30 different antimicrobial agents.
- Testing was performed on both field isolates and the A22 EAE vaccine strain of Chlamydia psittaci (ovis).
- Antimicrobials were classified into four distinct groups based on their observed inhibitory and lethal concentrations.
Main Results:
- No significant differences in antimicrobial susceptibility were observed between the field strains and the A22 EAE vaccine strain of Chlamydia psittaci (ovis).
- Antimicrobials were categorized into four groups: Group A (no effect), Group B (bacteriostatic >100 mg/l), Group C (bacteriostatic ≤10 mg/l, bactericidal >10 mg/l), and Group D (bactericidal >0.5 mg/l).
- Group D agents demonstrated potent bactericidal activity at very low concentrations.
Conclusions:
- Antimicrobial susceptibility is consistent between C. psittaci field and vaccine strains, simplifying treatment considerations.
- The categorization of antimicrobials provides a framework for selecting effective agents against C. psittaci.
- The study highlights the importance of appropriate antimicrobial selection for the diagnosis and successful therapy of ovine chlamydial abortion, potentially reducing economic losses in sheep production.